Forced deployment sequence

ABSTRACT

A fixed sequence activation handle is described that forces a predetermined activation sequence. Such handles are suitable for use in the delivery of medical devices or for other application that require a fixed sequence of activations.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims benefit to U.S. Provisional Patent ApplicationSer. No. 61/145,693 filed Jan. 19, 2009, which is incorporated byreference herein for all purposes.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to a tool having a fixed sequence of activationsteps. In particular the invention relates to medical device deploymenthandles that intend to eliminate practitioner errors of deliverysequence in deployment of a medical device.

2. Discussion of the Related Art

Endovascular medical devices that require a specific series of steps tocomplete the delivery are known in the art. For example the vascularprosthesis disclosed in U.S. Pat. No. 5,554,184 to Nazari has severalcontrol lines that are required to be activated in a particular sequenceto affect proper deployment of the device. Nazari does not disclose atool or operational handle that fail-safes the deployment sequence.Similar medical devices requiring a specific sequence of control linemanipulations for proper deployment are disclosed in WO 97/48350 toLauterjung and in U.S. Pat. No. 5,776,186 to Uflacker. Neither of thesereferences discloses a tool or operational handle that would force theproper sequence of pull line manipulations.

There are a variety of medical device delivery handles, tools, aids,etc. used to implant endovascular devices. Examples of such deliverytools are used in steerable catheter systems, where one or more pulllines act as tendons. When pulled, the pull line deflects a portion ofthe catheter (normally the far distal end). The deflection of thecatheter allows the precise navigation of the catheter through complexvasculature. Other medical device delivery handles provide a mechanicaladvantage to the pulling of a tether line or retraction sheath, usedwith self-expanding intravascular devices such as stent grafts. See forexample U.S. Patent Application 2005/0080476 to Gunderson et al., for ahandle that provides a mechanical pull advantage. Other embodiments oftools used to deliver implantable medical devices include simpleluer-lock fittings that have pull lines attached to luer members. When amember is removed from the luer fitting the pull line is activated. Seefor example U.S. Patent Application 2002/0151953 to Chobotov et al. Astypical in the art, the luer-lock and member arrangement as disclosed byChobotov et al. are not interlocked; that is the multiple activationcords/rods can be activated in any sequence. In such non-interlockedsystems, training, visual aids and labeling are typically used toencourage the proper delivery sequence. Despite the substantial effortsused to encourage the proper step sequencing, inadvertent user errors dooccur.

SUMMARY OF THE INVENTION

The invention provides an interlocked control handle that forces apredetermined activation sequence. Control handles according to thepresent invention are suitable for use in the delivery of medicaldevices.

In particular the present invention provides a fixed sequence activationsystem, comprising at least a first removable member attached to adistally extending line for communication with a remotely locateddeployable device; and a second member attached to a distally extendingline for communication with a remotely located deployable device toprovide a fixed sequence activation of the deployable device.

Additional features and advantages of the invention will be set forth inthe description or may be learned by practice of the invention. Thesefeatures and other advantages of the invention will be realized andattained by the structure particularly pointed out in the writtendescription and claims hereof as well as the appended drawings.

It is to be understood that both the foregoing general description andthe following detailed description are exemplary and explanatory and areintended to provide further explanation of the invention as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings are included to provide a furtherunderstanding of the invention and are incorporated in and constitute apart of this specification, illustrate embodiments of the invention andtogether with the description serve to explain the principles of theinvention.

In the drawings:

FIGS. 1A and 1B are perspective views of a handle assembly and medicaldevice according to one embodiment of the present invention.

FIGS. 2A and 2B show perspective views of a handle assembly and themedical device assembly during the first stage of deployment.

FIGS. 3A and 3B are perspective views of a handle assembly along with apartial side view of the distal portion of the medical device, showingthe positional manipulation of the medical device along with theretraction and release of the device anchors.

FIG. 4 is a partial perspective view of the distal portion of the selfexpanding medical device, showing details of the second control line.

FIGS. 5A and 5B are perspective cut-away views of a handle showing thefixed pulling sequence of the second and third control line.

FIGS. 6A and 6B are perspective views of a handle and a side view of themedical device showing the removal of the second and third controllines.

FIGS. 7A and 7B are perspective views of a handle and medical deviceshowing the activation of the fourth control line.

FIG. 8 is a perspective view of a handle showing a safety access portal.

FIGS. 9A through 9F show partial top and partial side cross-sectionalview of a device and method used to secure a control line to anattachment feature or substrate.

FIGS. 10 A through 10 D show top, perspective and cross-sectional viewsof a test fixture used to evaluate a retention feature of the presentinvention.

DETAILED DESCRIPTION OF THE ILLUSTRATED EMBODIMENTS

The invention is directed to a handle used to deliver a medical device,wherein the handle aids a practitioner in performing a fixed sequence ofactivation steps. In its simplest form the handle comprises a firstremovable member attached to a first distally extending line forcommunication with a remotely located deployable device; and a secondmember having an adjustment feature to modulate the deployable device.The second member is at least partially covered by the first removablemember and is attached to a second distally extending line forcommunication with the remotely located deployable device.

Another aspect of the device provides a handle which comprises a firstremovable member attached to a first distally extending line forcommunication with a remotely located deployable device; a secondremovable member having a rotatable portion, the second member at leastpartially covered by said first removable member and attached to asecond distally extending line for communication with the remotelylocated deployable device; and a third member at least partially coveredby said second removable member and attached to a third distallyextending line for communication with the remotely located deployabledevice.

The members may take the form of a removable member and/or movablemember. Examples include, but are not limited to, a wire, a covering, aknob, a knob assembly (a knob with additional components within theknob), a pin, cap, lid, sheet cover (e.g. a tape), hook, switch, orother structure for encouraging the order of removal and/or activationof distally extending lines. Said first, second, third or additionalmembers can be a combination of any of the above listed types of membersor any other structure. Said members can be attached to distallyextending lines. Members can be removed and/or moved by, inter alia,rotation, pulling, pushing, pressing, bending, unsnapping, breaking orany other method of removing and/or moving a member and still be able toactivate a distally extending line. In one aspect, said member can covereach other (i.e. nest within other members). In another aspect, saidmembers prevent another member from being removed and/or moved beforeanother member is removed and/or moved. The fixed sequence activationhandle may further comprise a port which allows access to at least oneof the first, second, third or additional distally extending lines.

In another aspect, the fixed sequence activation handle has at least afirst, second and third removable member each attached to a distallyextending line in communication with a remotely located deployabledevice having a first and second portion wherein removal of the firstmember from the handle results in partial deployment of the firstportion of the remotely located deployable device thus allowing accessto the second member. The second member can include a rotatable portionwherein rotation of said rotatable portion modulates the first portionof the deployable device and wherein removal of said second memberresults in complete deployment of the first portion of the device andallows access to the third member. Manipulation of the third memberdeploys the second portion of the device. In another aspect, thepresence of the first member prevents removal and/or moving of thesecond member. In another aspect, the presence of the second memberprevents the removal or moving of the third member. In another aspect,the third member is nested within the second member and the secondmember is nested within the first member. In another aspect, saidremovable members can be tethered together for easily accounting for theremoved components by the medical/delivery team. In another aspect, asystem for placing each removed component in a holder so that theremoved member can be readily accounted for is also contemplated.

Also provided is a method of delivering a deployable device comprisingthe steps of: providing a handle having at least a first, second andthird removable member each attached to at least one distally extendingline for communication with a remotely located deployable device havinga first and second portion; delivering the deployable device to a targetlocation; removing the first member from the handle to partially deploythe first portion of the device and allow access to the second member;rotating a rotatable portion of the second member to modulate the firstportion of the deployable device; removing the second member to completedeployment of the first portion of the device and allow access to thethird member; and manipulating the third member to deploy the secondportion of the device resulting in delivery of the deployed device.

For the illustrative purposes, FIGS. 1 through 7 provide detailedexamples of a medical device and delivery sequence. The sequence stepsare dictated and fixed by the design of the delivery handle. To addclarity, FIGS. 1 through 7 show the various stages of the handleactivation along with a corresponding view of a typical medical deviceas it is being deployed.

FIGS. 1A and 1B are perspective views of a handle assembly according toone embodiment of the present invention. FIG. 1B is a side view of amedical device to be deployed. Shown (at FIG. 1A) is a handle assembly100, having a catheter 102. The catheter 102 extends to a medical deviceassembly 104. A portion of the catheter is shown removed to expose theinternal control lines. The medical device shown is a self expandingstent graft that is held in a constrained state by two separateconstraining sheaths 106 and 108. Each of the constraining sheaths havea “rip-cord” stitch 110 and 112. Stent grafts and constraining sheathscan be fabricated according to the methods and materials as generallydisclosed in, for example, U.S. Pat. No. 6,042,605 issued to Martin, etal., U.S. Pat. No. 6,361,637 issued to Martin, et al. and U.S. Pat. No.6,520,986 issued to Martin, et al. At the far distal end of the medicaldevice is an olive 114. A guide wire lumen 116 exits the distal end ofthe olive and extends through the catheter 102 and through the handle100. A guidewire is typically used during the delivery of the medicaldevice but has been omitted from the Figures for clarity. Containedwithin the catheter 102, are four individual control lines 120, 122, 124and 126. These control lines will subsequently be used to affect thedeployment of the medical device. Also shown is a first member 128,removably attached to the handle assembly 100.

FIGS. 2A and 2B show perspective views of the handle assembly 100 andthe medical device assembly 104 during the first stage of deployment. Toaffect the first stage of deployment, the first member 128 is rotatedaccording to direction arrow 202 and then pulled along direction arrow204. Attached to the first member 128 is the first control line 120.When the first member 128 is pulled, the first control line 120 ispulled along direction arrows 206. The first control line 120“un-stitches” the distal constraining sheath 106 as it is being pulled,allowing the distal portion of the stent graft to self expand in thedirections indicated by arrows 208. The first member 128 is pulled untilthe distal constraining sheath is fully un-stitched. By pulling furtheron the first member, the first control line 120 is fully removed fromthe catheter/handle and is discarded. While in the state depicted inFIG. 2, the medical device assembly 104 is still attached to thecatheter 102 by the proximal constraining sheath 108. Also while in thestate depicted in FIG. 2, the medical device anchors or barbs 210 are ina withdrawn or contracted state.

FIG. 3A is a perspective view of the handle assembly 100 along with apartial side view of the distal portion of the medical device 104 (FIG.3B). When the first member 128 (FIG. 2) was removed a second member 302was exposed. Fixed to the second member 302 is a rotatable portion 304,in the form of a knob. While in the states shown in FIGS. 2 and 3, theposition of the medical device within the vasculature can be preciselyadjusted. For example the handle assembly 100 can be translated alongdirection arrows 306 to move or adjust the medical device in alongitudinal direction 306. Similarly, the handle can be rotated asindicated by direction arrows 308 to cause a rotation of the medicaldevice. The longitudinal adjustment will allow precise alignment of themedical device to a specific target within the vasculature, for exampleto a position very close to but not occluding a side branch vessel. Therotational adjustment will also allow precise alignment of a bifurcatedor side branched device.

The longitudinal and rotational manipulations of the medical device arepossible due to the medical device attachment to the catheter along withthe device anchors being in a retracted state. When the medical deviceis precisely located at the target site, the device anchors can bereleased and allowed to engage the vascular wall. The release (orretraction) of the anchors is affected by rotating the rotatable portion304 in the directions indicated by arrow 310. When the rotatable portion304 is rotated, tension 312 is applied (or removed) to the secondcontrol line 122. Control line 122 is routed through the catheter and isthen threaded, in a “purse-string” fashion, around the distal anchorportion of the medical device. When tensioned, control line 122 willcause the anchors to retract. When rotatable portion 304 is rotated inan opposite direction, the tension on control line 122 is relaxed,allowing the anchor portion of the device to self expand in thedirection indicated by arrows 314, thereby engaging the anchors into thevasculature wall.

After the precise alignment of the medical device and the engagement ofthe device anchors, the second control line 122 must be removed. Shownin FIG. 4 is a partial perspective view of the distal portion of theself expanding medical device 104, showing details of the second controlline 122. The second control line 122 is shown contained within a smalltube 402 that is attached to the catheter shaft 102 (not shown). Thesecond control line 122 is shown threaded through the stent graft in apurse-string fashion. The second control line 122 terminates with a loop404 that is captured by a third control line 124. When the third controlline 124 is pulled in the direction indicated by arrow 406, the loop 404is released, allowing the second control line 122 to be pulled in thedirection as indicated by arrow 410. The second control line 122 is thenfurther pulled and remove from the medical device.

In order to remove the second control line 122 from the medical device,the third control line 124 must be pulled first (to release to secondcontrol line loop). This sequence of pulling the two control lines isaffected by the handle mechanism depicted in FIGS. 5A and 5B. The thirdcontrol line 124 is directly attached to the rotatable member 302, sothat when member 302 is initially rotated in the direction indicated byarrow 502, the third control line 124 is pulled to release the loop 404(FIG. 4). In order to rotate member 302 an interlock button 503 must bemanually activated. The second control line 122 is contained within arigid tube 504. Thus when the member 302 is rotated, the rigid tube 504is rotated as shown in FIG. 5B. The second control line 122 is thereforenot further tensioned since the rigid tube maintains a constant length.Therefore the rotation of member 302 will result in a differentialmotion between the third control line 124 and the second control line122. After member 302 is fully rotated both control lines 122, 124 canbe simultaneously translated. This mechanism can be used to activatemore than two control lines.

As shown in perspective at FIG. 6A and partial side view at FIG. 6B, thesecond member 302 with the attached rotatable portion 304 can then beremoved by pulling in the direction indicated by arrow 602. As themember 302 and rotatable portion 304 are pulled, the two control lines122 and 124 are pulled and fully removed from the device, catheter andhandle. The member 302 and rotatable portion 304 are interlocked so thatthey cannot be removed from the handle unless the knob is fully rotatedto allow full expansion of the medical device anchors. The knob rotationcauses a follower nut to translate to a home position which in turnreleases an interlock to allow subsequent removal of the second member302. Additionally there can be a secondary interlock, such as a buttonthat must be manually activated to allow removal of the second member302. After complete removal of the second member 302 and any attachedcontrol lines the distal portion of the medical device 104, partiallyshown in FIG. 6, is fully deployed with the anchors 210 fully engagingthe vascular wall 604.

As shown in perspective views of FIGS. 7A and 7B, the secondconstraining sheath 108 can be released by the removal of a third member702. The fourth control line 126 is attached to the third member 702, sothat when the third member is pulled in the direction indicated by arrow704, the fourth control line 126 is pulled in the direction indicated byarrow 706. When pulled, the fourth control line 126 “un-stitches” thesecond constraining sheath 108, allowing the medical device to selfexpand in the direction as indicated by arrow 708. The third member 702and attached fourth control line 126 can then be fully removed from themedical device, catheter and handle. The medical device 104 is now fullydeployed and is no longer attached to the catheter 102. The handle cantherefore be pulled in the direction indicated by arrow 710, removingthe catheter from the vasculature and completing the deployment phase ofthe procedure. The second constraining sheath 108 can be optionallyattached to the catheter or be allowed to remain in the vasculature.

As shown in the perspective view of FIG. 8, the handle assembly 100 canincorporate an access portal 802, allowing manual access to the variouscontrol lines if required. The access portal 802 can be exposed ifdesired by the removal of cover 804. The various control lines can beidentified by colors, alpha-numeric markings, ordered locations,different sizes or shapes or any other indentifying means. The controllines can incorporate features to allow grasping and manipulations ofthe lines by commonly available tools.

The present invention is not limited to the use of members as detailedabove. Various other means of providing a forced, interlocked activationsequence are possible. For example the interlocked activation mechanismscan include levers, slide-mechanisms, plugs, sequentially pulled tubes,sequentially released locks. Referring to FIGS. 1 through 7, the presentinvent broadly provides an interlocked activation system that comprisesa first, second and third mechanism each having a pre and postactivation state. A first mechanism (first member 128) is in apre-activation state as shown in FIG. 1 and is in a post-activationstate as shown in FIG. 2. A second mechanism (second member 302) is in apre-activation state as shown in FIG. 3 and is in a post-activationstate as shown in FIG. 6. A third mechanism (third member 702) is in apre-activation state as shown in FIG. 6 and is in a post-activationstate as shown in FIG. 7.

The interlocked activation system of the present invention initiallyallows only the first mechanism to transition from the pre to postactivation state; the first mechanism (first member 128) is the onlyactivation mechanism initially exposed and is the only mechanism membercapable of being activated.

A transition of the first mechanism from the pre to post activationstate allows only the second mechanism to transition from the pre topost activation state; after the first member is removed only the secondmechanism (second member 302) is exposed and is member capable of beingactivated.

A transition of the second mechanism from the pre to post activationstate allows only the third mechanism to transition from the pre to postactivation state; after the second member is removed, only the thirdmechanism (third member 702) is exposed and is member capable of beingactivated.

The present invention is not limited to interlocked sequences that usecontrol lines. For example the concepts of the present invention caninclude interlocked devices that activate electrical contacts. Suchcontacts can rely on the conductance of the various handle components sothat an electrical contact is opened when a particular handle componentis removed. The manipulation of a particular handle component could alsoactivate a simple electrical switch. The manipulation of a particularhandle component could also activate proximity sensors, pressuresensors, fluid flow sensors or other type sensors. Combinations ofvarious activators can also be incorporated into the designs of thepresent invention. For example control lines could be combined withelectrical switches. In addition to handles or hand-held pendants, thevarious concepts of the present invention can also be incorporated intocontrol panel activation devices.

Typical handles, tools or catheters used to deliver medical devices cancomprise commonly known materials such as Amorphous CommodityThermoplastics that include Polymethyl Methacrylate (PMMA or Acrylic),Polystyrene (PS), Acrylonitrile Butadiene Styrene (ABS), PolyvinylChloride (PVC), Modified Polyethylene Terephthalate Glycol (PETG),Cellulose Acetate Butyrate (CAB); Semi-Crystalline Commodity Plasticsthat include Polyethylene (PE), High Density Polyethylene (HDPE), LowDensity Polyethylene (LDPE or LLDPE), Polypropylene (PP),Polymethylpentene (PMP); Amorphous Engineering Thermoplastics thatinclude Polycarbonate (PC), Polyphenylene Oxide (PPO), ModifiedPolyphenylene Oxide (Mod PPO), Polyphenelyne Ether (PPE), ModifiedPolyphenelyne Ether (Mod PPE),Thermoplastic Polyurethane (TPU);Semi-Crystalline Engineering Thermoplastics that include Polyamide (PAor Nylon), Polyoxymethylene (POM or Acetal), Polyethylene Terephthalate(PET, Thermoplastic Polyester), Polybutylene Terephthalate (PBT,Thermoplastic Polyester), Ultra High Molecular Weight Polyethylene(UHMW-PE); High Performance Thermoplastics that include Polyimide (PI,Imidized Plastic), Polyamide Imide (PAI, Imidized Plastic),Polybenzimidazole (PBI, Imidized Plastic); Amorphous High PerformanceThermoplastics that include Polysulfone (PSU), Polyetherimide (PEI),Polyether Sulfone (PES), Polyaryl Sulfone (PAS); Semi-Crystalline HighPerformance Thermoplastics that include Polyphenylene Sulfide (PPS),Polyetheretherketone (PEEK); and Semi-Crystalline High PerformanceThermoplastics, Fluoropolymers that include Fluorinated EthylenePropylene (FEP), Ethylene Chlorotrifluroethylene (ECTFE), Ethylene,Ethylene Tetrafluoroethylene (ETFE), Polychlortrifluoroethylene (PCTFE),Polytetrafluoroethylene (PTFE), Polyvinylidene Fluoride (PVDF),Perfluoroalkoxy (PFA). Other commonly known medical grade materialsinclude elastomeric organosilicon polymers, polyether block amide orthermoplastic copolyether (PEBAX) and metals such as stainless steel andnickel/titanium alloys.

Typical methods used in the assembly of handles include commonly knowntechniques used to attach two or more components. Examples of permanentattachments include the use of glues, adhesives, welds, insert molding,heavy press-fits, one-way snap or lock features, pressed pins, heatstaking and rivets. Examples of semi-permanent attachments or those thatrequire a tool to separate the components include screws, threadedfasteners, snap-rings and snap-fits. Examples of releasable attachmentsor those that can be separated by hand without the use of an additionaltool include snap-fits, twist lock features, push to release features,squeeze to release features, slide levers, latches and light press-fits.

Control lines can comprise commonly known high tensile strengthmaterials such as carbon fibers, liquid crystal polymers and metalwires. Control lines can have various cross-sectional profiles such ascircular, oval, rectangular or other polygon shapes. Control lines canalso incorporate external lubricious layers, lubricious coatings orlubricious wrappings to minimize friction.

Control lines can be attached to handle or activation mechanisms by avariety of commonly know methods such as wrapping a control line arounda pin or by securing a line by screws. Other methods include threading aline through a small hole and then tying knots or securing aprotuberance to the end of the control line so that theknot/protuberance cannot be pulled through the small hole. Adhesives,clamps, crimps, pinch mechanisms, heat staking, insert molding and othercommon attachment methods could also be used for control lineattachments. Alternatively, a control line or cable retention system maybe used to secure the wires inside the handle. The system comprises atleast one retaining element; a substrate having a cavity dimensioned toallow an insertion of the at least one retaining element; a first slotextending from a first edge of the substrate to said cavity; and asecond slot extending from a second edge of the substrate to said cavitywherein the first and second slots are dimensioned to allow a placementof an elongate member, such as a wire, within the slots so that theretaining element retains the elongate member in the cavity. Theretaining element may be a ball bearing, a spherical element, acylindrical post, or other such means used to deform the elongatemember. The cavity extends to a depth below that of the depth of thefirst and second slot to create a space in which to deflect or deformthe wire into using the retaining element. The cavity may be of anysuitable dimension of shape or size so that a retaining element maysecure the wire into the substrate cavity. It is desired to provide acavity diameter that is smaller than that of the retaining element toallow a force fit. If desired an adhesive may be placed in the cavityprior to and/or after deforming the wire into the cavity so that anadded securement means is provided. In order to retain an elongatemember such as a wire in a device the following steps may be utilized. Adevice handle having a substrate with a cavity, a first slot and asecond slot is obtained such as shown in FIG. 9A-9F. At least oneelongate member is positioned within the first and second slot to crossthe cavity. At least one retaining element is positioned within thecavity so that the at least one elongate member is secured between theretaining element and the substrate. The elongate member is deformed bythe retaining element such that it is secured in position between theretaining element and the substrate.

This simple, easy to assemble, easily automatable, visually verifiableand high strength joining concept is disclosed in FIGS. 9A through 9F.Shown in FIG. 9A is a partial top view of a control line attachmentfeature 900 while FIG. 9B displays a partial cross-sectional side viewtaken along plane A-A. Shown is a circular cavity 902 terminating in aspherical shape 904. A first slot 906 and a second slot 907 have beenformed through the attachment feature and penetrate the circular hole.The slots 906 and 907 are shown as centered on the cavity 902centerline. The slots may optionally be located at non-centeredpositions on the cavity. As shown in FIG. 9B, optionally, the slot 906“dives into” the edges 908 of the circular bottom of the cavity 902,forming a curved channel when viewed along cross-sectional plane A-A.

As shown in FIGS. 9C and 9D, a control line 910 is placed into the firstslot 906. Referring to FIGS. 9E and 9F, to secure and fix the controlline to the attachment feature, a retaining element 912 is pressed intothe cavity 902 along the direction indicated by arrow 914. When fullyseated the rigid sphere deforms the control line into the shape of thecurved channel. The interference, press fit between the cavity 902, andthe retaining element 912 effectively secures the control line onto theattachment feature. The control line can then be bi-directionallytensioned 916 without slipping or dislodging from the attachmentfeature. If desired, an adhesive can be applied to the exposed portionof the rigid sphere to further enhance the retention of the controlline. Optionally, the exposed portion of the cavity can also be“heat-staked” or deformed to further constrain the rigid sphere andcontrol line. Optionally, the cavity 902 can incorporate retainingelement alignment guides such as raised vertical shoulders, chamfers,funnels or other means to align the retaining element to the hole.

The attachment feature 900 can be fabricated from commonly knownplastics or metals as listed above. The retaining element 912 can be ametallic ball bearing, a plastic sphere or a ceramic/glass sphere. Arigid roller or cylinder shaped element can be used in place of therigid sphere to secure ribbon shaped control lines. Other rigid elementshapes and matching holes can be used to attach various elementstogether as desired. A rigid element can also be transparent to allowvisual inspections.

Attachment features of the present invention can also be used to secureelectrically conductive materials such as wires or cables. Attachmentfeatures of the present invention can also be used to securenon-electrically conductive materials such as fiber optics, silks,polymers or natural bio-materials such as blood vessels or nerves.

The attachment feature can also be used to release a cord or cable at apredetermined load. For example the attachment feature substrate, cable,and retaining element can have various tolerances, a specific hardnessor specific surface features that, in combination, result in apre-determined retention load.

EXAMPLES Example 1

A fixture, according to one embodiment of the present invention, wasfabricated to test cable retention forces. As shown in top view FIG. 10Aand perspective view 10B, an attachment feature 1000 was assembledhaving a substrate 1002. The substrate 1002 had a cavity 1006, sized toaccept a cable 1008 and a retention sphere 1004. FIGS. 10C and 10D aresectional views taken along the centerline of cavity 1006. As shown, acable 1008 was placed into the cavity 1006. A ball bearing 1004 was thenpressed into the cavity 1006, deforming the cable as shown in FIG. 10D.A medical grade UV curable adhesive was then dispensed into the cavity,partially enmembersulating the cavity, ball bearing and the deformedcable.

Example 2

The fixture from Example 1 was fitted with cable sections, ball bearingswere pressed into the cavities and an adhesive was applied as anovercoat. The compressive loads required to press and seat the ballbearings were recorded using an Ametek® (Paoli, Pa.) Chatillion® DFX-050compression gage. After curing the adhesive, the cables were tensionedto determine the retention load. The cables were tensioned using anInstron® (Norwood, Mass.) tensile tester and load cell. Twentyassemblies were evaluated.

While particular embodiments of the present invention have beenillustrated and described herein, the present invention should not belimited to such illustrations and descriptions. It should be apparentthat changes and modifications may be incorporated and embodied as partof the present invention within the scope of the following claims.

1. A fixed sequence activation handle comprising: a. a first removablemember attached to a first distally extending line for communicationwith a remotely located deployable device; b. a second removable memberhaving a rotatable portion, the second member at least partially coveredby said first removable member and attached to a second distallyextending line for communication with the remotely located deployabledevice; c. a third member at least partially covered by said secondremovable member and attached to a third distally extending line forcommunication with the remotely located deployable device.
 2. The fixedsequence activation handle of claim 1, wherein the presence of the firstmember prevents the removal of the second member.
 3. The fixed sequenceactivation handle of claim 1, wherein the presence of the second memberprevents the removal of the third member.
 4. The fixed sequenceactivation handle of claim 1, wherein the third member is nested withinthe second member; and the second member is nested within the firstmember.
 5. The fixed sequence activation handle of claim 1, wherein thethird member is removable.
 6. The fixed sequence activation handle ofclaim 1, further comprising an access port to at least one of saidfirst, second or third distally extending lines.
 7. A fixed sequenceactivation handle comprising: a. a first removable member attached to afirst distally extending line for communication with a remotely locateddeployable device; and b. a second member having an adjustment feature,said second member at least partially covered by said first removablemember and attached to a second distally extending line forcommunication with the remotely located deployable device.
 8. A fixedsequence activation handle comprising: at least a first, second andthird removable member each attached to a distally extending line incommunication with a remotely located deployable device having a firstand second portion; wherein removal of the first member from the handleresults in partial deployment of the first portion of the device andallows access to the second member; wherein the second member includes arotatable portion wherein rotation of said portion modulates the firstportion of the deployable device wherein removal of said second memberresults in complete deployment of the first portion of the device andallows access to the third member; wherein manipulation of the thirdmember deploys the second portion of the device.
 9. A method ofdelivering a deployable device comprising the steps of: a. providing ahandle having at least a first, second and third removable member eachattached to at least one distally extending line for communication witha remotely located deployable device having a first and second portion;b. delivering the deployable device to a target location; c. removingthe first member from the handle to partially deploy the first portionof the device and allow access to the second member; d. rotating arotatable portion of the second member to modulate the first portion ofthe deployable device; e. removing the second member to completedeployment of the first portion of the device and allow access to thethird member; and f. manipulating the third member to deploy the secondportion of the device resulting in delivery of the deployed device. 10.A cable retention system comprising: a. at least one retaining element;b. a substrate having a cavity dimensioned to allow an insertion of theat least one retaining element, c. a first slot extending from a firstedge of the substrate to said cavity; and d. a second slot extendingfrom a second edge of the substrate to said cavity wherein the first andsecond slots are dimensioned to allow a placement of an elongate memberwithin the slots so that the retaining element retains the elongatemember in the cavity.
 11. A method of retaining an elongate member in adevice handle comprising the steps of : a. providing a device handlehaving a substrate with a cavity, a first slot and a second slot b.positioning at least one elongate member within the first and secondslot to cross the cavity; and c. positioning at least one retainingelement within the cavity so that the at least one elongate member issecured between the retaining element and the substrate.